Improvement in hydraulic governors



UNITED STATES PATENT GEETGE,

JAMES E. GILLESPIE, OF BOSTON, MASSA'OHUSETTS, ASSIGNOE TO GIL- LESPIEGOVERNOR COMPANY, OF SAME PLACE.

IMPROVEMENT IN HYDRAULIC GOVERNOROS.

Specification forming part of Letters Patent No. 57,630, dated August28, 1866.

To all whom it may concern:

Be it known that I, J AMES E. GILLESPIE, of Boston, in the county ofSuffolk and State of Massachusetts, have invented certain new and usefulImprovements in Hydraulic Regulating-Governors; and l do hereby declarethat the following, taken in connection with the drawings whichaccompany and form part of this specication, is a description of myinvention sufficient to enable those skilled in the art to practice it.

This invention relates to certain improvements upon and modifications inthe hydraulic governor which, under the number 34,055, was patented tomein the United States, Jannary 7, 1862. y

l/Vhile the construction shown and described in my said patent wouldgovern the speed of the mechanism therewith connected so as to confinethe speed within iixed maximum and minimum limits, yet within thoselimits the Velocity of the mechanism was not well regnlated, as slightchanges in the amount ot work to be performed would canse the governorso to operate as to allow a considerable change in the speed of theconnected mechanism within the maximum and minimum limits.

To economize the expenditure of the force applied-as, for example,pressure of steam or a head oi' waterand to regulate the velocity of themechanism thereby driven to an almost 4constant speed, instead of merelygoverning the same by coniining it within certainV limits, but allowingthe speed to vary or change within such limits, is the object of part ofmy invention.

Another object of another part of my invention is to so connect thegoverning` and regulating apparatus with the gate or valve or otherobject operated thereby that, while the parts may be disconnected atpleasure to an apparatus embodying it, as illustrated in theaccompanying drawings, of whichi Figure l is a plan of said apparatus.Fig. 2 is aside elevation; and Fi g. 3 is a sectional View of thepart'containing the cylinders and their pistons, the section being takenin the plane of the line z z, seen in Fig. l, except the lower left-handcorner, where the section is taken on the line y y, seen in said figure,

c is a case suited for containing an ordinary centrifugal pump, saidcase being' surmonnted with another, marked b, this containing areservoir for uid, as well as two cylinders, one, c, larger than theother, d, both being fitted with pistons marked, respectively, e and f,the pistone iitting looselyr in its cylinder, and the piston j' fittingclosely, but so as to slide freely, in its cylinder. The pump-case a isprovided with an inlet at the center, by which iluid is supplied, to beacted on by the pump; also, with an outlet for discharge of the supplieduid. All this, however, being as is common in centrifugal pumps, is notshown in detail in the drawings. The inlfet of the pump connects withthe reservoir part g of the case b, and the discharge-outlet of the pumpconnects with the open lower end of cylinder c, so that, as will beevident, the pump constantly circulates the fluid through the partsbefore described. At the upper part of cylinder c is an openingcommunicating with the fluid-reservoir g, and between the cylinders cand d, at the upper part thereof, is an opening, ln the case b, andbetween the cylinders c and d, is drilled a hole, j, this receiving ascrew-spindle, k, the end of which controls by its adjustment theaperture l, and a small passage (not seen in the drawings) connects jwith the cylinder d. The cylinder ting down upon a iiange on the insideof the top of case c, so that the only communication of fluid therewithmust be had through the passages described. The rod of the piston epasses up through the head of cylinder c, and carries a slottedcross-head or yoke, m, one portion of which surrounds the rod f ofpiston f, which is made with a considerable eX- tension above the caseb, the yoke m being fitted to slide freely upon the rod f', to which dand hole j are supplied with bottoms by tit is so connected by thespiral spring n that thereto, and the case b, the cylinders, and

piston c may move either up or down Without immediate movement of pistonf, compressing or extending the spring n, which then, acting to regainits normal condition, moves the pistons fand c to regain their normalposition relative to each other.

It is in t-he combination of the pistons @and f with the spring a, so asto operate in the manner as hereinafter described, that the chief partof the invention herein described consists.

The shaft o, rotated .from the machinery to be regulated through thebelt-Wheel p, drives the shaft q ofthe centrifugal pump by means of thespur-gear r and its pinion s, and on shaft o is an eccentric, t, which,rotating in the slot or opening made in lever or rocker a, vibrates itand the balanced notched bar v, which is pivoted thereto.

One end of the bar t is notched on its upper and lower edges (see Fig.2) with teeth somewhat like the teeth ot' a ratchet-Wheel, so that Whilebar c is reciprocating` it will, if its notched end is raised, engagewith the teeth on its upper edge the slide 11:,Which is arranged to moveon ways w, and will push the slide w away from the lever u. If said endof bar v is depressed, then the teeth on its lower edge, engaging withslide w, will, in the reciprocations of r, pull the slide w toward thelever u.

The pin a in the bar v, extending into the slotin m, is themeans bywhich the notched end of 'u is raised and lowered, the slot in m beingmade long enough to permit the vibrations of pin a', caused by theoperation of the eccentric t.

The slide w abuts against the end of a rack marked b', which is-iittedso asto slide freely, and in sliding to turn a spur-gear, c', thc shaftof which, by suitable connections, Works the valve of a steam-engine,the gate of a Waterxvheel, or the controlling device of any mechanismthe speed of which it is desirable to regulate.

On the slide w is hinged a latch, d', which, when placed over aprojection, c', from the rack b', draws the raclc in the same directionin which the slide 'w is pushed by bar c. And it may be here observedthat the shaft of c is connected in a manner such that, supposing thegate of a Water-wheel to be the object controlled thereby, it would beshut by the pulling of rod o on the slide w, and opened by the pushingof the same, so that, in case latch d should be disconnected from theprojection e, in order that the Water-gate might be closed by hand, theregulator would, by the abutment of slide w against the rack b', stillbe in condition to prevent increase of speed, though not in suchcondition as to be able to maintain the normal speed. It is in thisarrangement of parts, which operates to free the governor from itscontrolling action in one di rcction, while its control is maintained inthe opposite direction that another part ot' my invention-consists.

The pump-case andthe passages' leading passages therein, heilig filledwith oil or other suitable fluid, and the mechanism the speed of whichis to be controlled being connected With the governor by belting ontothe pulley 19,1't is evident that the iiuid in the cases a and b Will becirculated With a velocity corresponding to the speed given to the pump,the fluid-current,'impinging against the bottom'of piston c and passingits sides, or through openings through it, will overcome its gravitywhen the velocity of the current is sufficient for that purpose, andwill cause the piston e to rise in itscylinder, the fluid above thepiston and that moving beyond it passing through the opening It into g,and thence to the inlet of the Dump.

Rotation of shaft o reciprocates the bar c, which is nicelycounterbalanced, as shown, the notched end of the bar being so curvedthat it will reciprocate freely in the opening in the cross-head wbetween the plates f and g', in whatever position the bar o is madev toassume by its connection with the piston e, so long as in that positionthe mechanism runs at its normal speed; but when the speed is increasedthe piston e, ascending, depresses the notched end of bar u till itengages with g, moving the rack b', this operating to shut theWater-gateor steam-valve with which it is connected. Decrease ot the normal speedcauses descent of piston e, this elevating the notched end of bar o tillit engages with f' and pushes the rack b in a direction away from thecases, this operatin g to open the said gate or valve. Y

Such is the general operation of the machine, it being substantially, sofar asy described, that of the apparatus shown in my patent beforereferred to, except that the main cylinder is not perforated, as thereindescribed, other and better means being herein supplied for effectingall and more than was eifected by the perforations of the cylinder in mysaid patent.

In the construction shown in my aforesaid patent the governing actionwas defective in the same manner that the action of the common ball orcentrifugal governors is defect ive-that is to say, that it requires notonly an increase of speed to close the valve or gate connectedtherewith, but to hold it closed, and a decrease of speed to open andhold open such valve or gate, the consequence being the eo'ntinuedvibration or change of speed above and below the normal rate.

But by the addition of the spring m, acting to resist change ofpositionin either direction, together with the gradually-yielding springholder,the operation of increase of speed ot the mechanism is iirst to raisethe main piston compressing the spring, the result being' the closing ofa valve or gate; but to maintain the main piston at the elevationrequired to -keep the gate closed does not call for the maintenance oi'the speed required to raise the main piston, for the reason' that thespring on, asserting its force to return to its normal position, raisesthe gradually-yielding piston f, and, all the parts being then inequilibrium, the normal speed will be maintained till some change in thecondition ofthe applied force or of the work to be done occurs to changethe position of the main piston. Snpposing the force of the motor to bedecreased, or the amount of work to be increased, causing a retardationof speed and a consequentlowering of the main piston, this elongatingthe spring a, the piston f, by the pull of the spring in its effort toassume its normal condition, will quickly assume its normal posit-ion,and, the parts bein gthen all in equilibrium, the gate will remain inthe position required to run the mechanism at its normal speed tillchanges in the power applied or in the work done cause another change inthe position of the main piston. Thus it will be seen that a uniformspeed may be maintained with the valve'or gate partly opened or closed,while with any centrifugal or ball governor, or with my hydraulicgovernor, as shown in my aforesaid patent, the speed has to beconstantly kept above thenormal rate to keep the gate or valve closed,or below the normal rate to keep it open. v

Referring again to the drawings, more particularly to Fig. 3, for adescription ofthe operation of the pistonfand the spring a upon the mainpiston c, it will be seen that the piston f cannot be moved freelyupward any faster than thetluid can enter cylinder d to supply the spaceleft by such movement. Therefore the yoke m compresses spring a betweenit and the place 4where it is attached to the piston-rod f; or if thepiston c descends, it will be seen that the piston j" cannot descendfaster than the tluid can be forced out of the cylinder d, and that thespring n will be elongated between the yoke m and the place where itisfastened to j". But in either ease the spring m will cause the pistonftomove after the movement of piston e till j' assumes its normal` positionrelative to c, and the time which it takes to accomplish this isregulated by the position ofthe screw-plug 7c relative to the aperturel.

rlhe aperture i serves merely to let any huid which may leak past thepiston f escape into the main cylinder c when j' moves upward. But theoperation ofspring a is exerted not alone on pistonf; it acts at thesame time on piston e, its function being, primarily, to restore theposition of the pistons fand e relative to each other after eachdisturbance or change of the position of piston e, and when saidrelation between the pistons is obtained the mechanism regulated inspeed thereby will move at the normal rate of speed to which it isadjusted, without regard to whether the pistons e and j are at the top,middle, or bottoln of their cylinders.

In some cases it may be desirable to impart to the slide w the regularreciprocating movement from the mechanism driven by the motive power,instead of giving such regular movement to the lever u and bar c. Insuch cases the gate or valve will be connected with the lever u, or itssubstitute, instead of with the slide w, as herein show/n.

ln my invention the position of the governor or the main piston e alwaysbears a definite relation to the position of the gate or valveultimately operated thereby. though the work of opening or closing suchgate or valve is not performed by the governor itself, this merelyindicating when the work ot' opening' and closing should be performedand causing it tobe done. For example, if the governor-piston e ismidway between t-hetop and bottom of its cylinder, the gate with whichit is connected is, when properly adjusted, half opened, and, as thepiston cis raised or lowered, so respectively is the gate lowered orraised, it being fully closed when the pisto-n e is at the top of itsstroke and fully opened when it is at the bottomof its stroke; and thischange ot' the gate is very quickly accomplished. Any variation from thenormal speed of the machinery to be regulated, operatin g to change thespeed of the pump, causes at once a change in the position of the pistonc, either compressing or elongating the spring a, according as thepiston e is raised or lowered, which spring, being attached to a supportwhich is practically for a moment nuyielding, prevents extreme movementsot' piston c. Said support, then yielding under the influence of thespring, gradually, as fast as the tluid can pass the graduated openingcontrolling the rate of its movement, brings all the parts of thegovernor into equilibrium, the Ispring a returning to its normalcondition as it moves its yielding support rIhe rst operation of anychange of speed from the normal one acting through the pumpdrivingmechanism is to quickly change the position ot' the gate to a closeapproximation of the position required to maintain the normal speed, andthe spring and its yielding support afterward operate to adjust orcorrect the position of the main piston, so as to make the slightchanges needed in the position of the gate to maintain the correctnormal speed. By adjustment'of the piecej the iiow of the fluidconsequent upon movements of the piston f can make the rate of speed ofsuch movements whatever may be desirable.

The cylinder d might be entirely closed and an opening made in or on oneside ot' the piston, so that the spring a, when not in its normalcondition of freedom from stress, would move the piston as fast as thefluid could pass such opening, and the graduations of such opening mightbe made in various ways more or less convenient. v Y

It is known that the ordinary ball-governor, when controllinga valve,does not keep it unusually closed unless the normal speed is not onlyincreased, but is kept at such increase. So, too, the valve is not keptthereby unusually y With-the cylinder d, its piston j', and the springu, or the equivalents of these, when arranged to operate togethersubstantially as specified. 2. In combination with the foregoing, a

passage eapableof variation, when so arranged as that by such variationthe rate of speed of the movement of the pist-on under influence of itsspring may be changed.

3. Combining a governor and theobject governed thereby insuch amannerthat, while the connection between the governor and the governedobject can be broken to prevent movement of the. latter in onedirection, the connection causing movement of the governed object in thereverse direction remains operative, substantially as shown anddescribed.

JAMES E. GILLESPIE.

Witnesses J. B. CROSBY, S. M. MCINTIRE.

